The invention relates to a touch-protected socket, a plug and a plug-in connection, in which electrical contact is established between the socket and the plug in the interior of the socket, which socket has a housing produced from an electrically insulating material.
AT 386 298 B discloses a connecting terminal for electrical conductors in which electrical contact is established between two electrical conductors within an electrically insulating housing, wherein a clamping spring prevents the electrical conductors from being pulled out. A trigger can be used to move the clamping spring to a tensioned state in which the electrical conductors can be inserted into the connecting terminal and to a state in which it is relieved of tension and the electrical conductors are prevented from being pulled out of the connecting terminal.
However, the existing prior art with respect to plug-in connections requires improvements in relation to simple operator control and assembly.
An object of the present invention is to provide a plug-in connection which is, first of all, touch-protected and, secondly, simple to control. This object is achieved by a socket, a plug, and a plug-in connection in accordance with embodiments of its invention.
According to one exemplary embodiment of the invention, a socket is provided. The socket comprises a housing which is composed of electrically insulating material and has an elongate plug-receiving region. A contact spring is arranged in the plug-receiving region. And, a lever in its open position, tensions the contact spring, so that a dimension of the contact spring transverse to the longitudinal direction of the plug-receiving region is reduced, and in its closed position, relieves the contact spring of tension relative to the tensioned state. That is to say, in the closed position of the lever, the contact spring has a lower pretension (for example a slight pretension or a state in which it is completely relieved of tension) than in the open position of the lever.
According to this exemplary embodiment, a contact connection can be established between the socket and the plug on the inner side of the components, wherein the outer sides are designed to be electrically insulating. This ensures touch-protection not only in the plug-connected state but also in the non-plug-connected state. Owing to the lever and its interaction with the contact spring, a force which has to be applied for the plug-in process is minimized and, nevertheless, a good contact force between the plug-connected components is ensured. The plug-in forces are furthermore independent of the normal contact force which can be achieved, so that high resulting normal contact forces can be achieved with a low operator control force.
According to a further exemplary embodiment of the invention, the socket is designed such that the lever, in the closed state, extends into an inlet opening in the plug-receiving region. Therefore, a plug in the plug-receiving region is prevented from being pulled out.
According to a further exemplary embodiment of the invention, the contact spring is fixedly connected to an electrically conductive connection to which an electrical line can be connected.
According to a further exemplary embodiment of the invention, the socket is designed such that the lever can be pivoted about a rotation axis and has a grip region, wherein an operating end of the lever, which operating end is situated on the opposite side to the grip region with respect to the rotation axis, tensions the contact spring.
According to a further exemplary embodiment of the invention, the contact spring comprises a component or structural element which is both resilient and electrically conductive.
According to a further exemplary embodiment, the contact spring is a bent leaf spring which has two ends which both point toward the same longitudinal end of the socket.
According to a further exemplary embodiment, the contact spring comprises one component which is resilient, and comprises another component which is electrically conductive. For example, a helical spring could form the resilient component and a structural element which is pretensioned by the helical spring could form the electrically conductive component. It is likewise possible for a non-conductive resilient material (for example an elastomer) to form the resilient component and for a material which is pretensioned by the non-conductive resilient material to form the electrically conductive component.
The invention furthermore provides a plug for a socket, wherein the plug has an electrically insulating housing and a clearance into which the contact spring of the socket can be inserted when the plug is inserted into the socket. Therefore, touch-protection is provided for all structural elements (plug and socket) in all situations which occur during operation and during assembly.
The invention further provides a plug-in connection having a socket according to one of the exemplary embodiments and a plug of this kind, wherein the contact spring is dimensioned such that, when the lever is open and as a result the contact spring is tensioned, the contact spring can be inserted into the clearance in the plug, and, when the lever is closed, the contact spring presses against an electrically conductive inner face of the clearance. In the process, the electrically conductive inner face of the clearance can be formed by sections of the housing, which are designed to be conductive in sections, or separate structural elements which are fixedly connected to the housing.
According to a further exemplary embodiment of the invention, the socket is designed such that, when the lever is closed, the lever engages behind the plug which is inserted into the plug-receiving region, so that the plug is prevented from being pulled out of the socket.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.